Sodium resonance fluorescence lidar applications in atmospheric science and astronomy

The mesospheric Na layer is generally confined to the region between 80 and 110 km, with a peak near the mesopause where the density ranges from about 10³-10⁴ cm^-3. The layer is an excellent tracer of wave motions, and Na lidar studies are now making important contributions to the gravity waves near the mesopause. In the field of astronomy, Ni lidar techniques are also being developed for creating artificial guide stars that can be used with groundbased adaptive telescopes to compensate image distortion caused by atmospheric turbulence. The design of modern Na resonance fluorescence lidars is described, and applications in atmospheric sciences and astronomy are discussed.